Have them test the strength of the capacitor for the compressor. May be weak and causing it to overheat. May have got lucky and it cooled off/reset when you stopped it.
Flush the outdoor coil with a garden hose and sprayer once a month. Have the freon checked once a year. Use window blinds/drapes/shades and shade trees to lessen the load on it. Seal up the attic hatch and door gaskets so they don't leak air in/out.
Sure. Most of those things need the compressor running in order to check them.Can these things be checked when the compressor is working properly? I sprayed water on it and it is working fine now.
I would bet good money that the txv screen is dirty. You would need the tech to come out again to diagnose this.